In order to achieve the trans-seasonal storage of dry maize straw (DMS) and utilization of vegetable wastes, the mixed airtight wet-storage of DMS and cabbage waste (CW) were implemented at 18 ± 1 ℃ for 60 days based on silage theory. The effects of different doses of acetic acid on the storage and fermentation quality of DMS and CW were investigated. The dynamics of their microbial community diversity during storage were also investigated using Illumina MiSeq high-throughput sequencing. Plant materials were divided into group ME (without the addition of acetic acid), group AA (with acetic acid added at a dose of 0.3%), and group AB (with acetic acid added at a dose of 0.6%), and then changes in their chemical composition, fermentation quality, and microbial community diversity were analyzed over 30-day intervals. The content of dry matter (DM), water soluble carbohydrates (WSC), and crude protein (CP) were significantly (P < 0.05) in group AA higher than those in group ME after 60 days, while the content of acid detergent fiber (ADF) and acid detergent lignin (ADL) were significantly (P < 0.05) lower in group AA compared with those in group ME. The content of hemicellulose (HC), cellulose (CL), and holocellulose (HOC) were significantly higher in group AA compared with those in group ME (P < 0.05). The pH was significantly (P < 0.05) lower in group AB than that in group ME after both 30 and 60 days, while the content of lactic acid in this group increased significantly (P < 0.05) after 30 days, and then decreased significantly (P < 0.05) after 60 days, compared with that in group ME. As a result, the ratio of lactic acid to acetic acid (LA/AA), the ratio of lactic acid to total organic acid (LA/TOA), and the ratio of ammonia nitrogen to total nitrogen (AN/TN) in groups AA and AB were lower than those in group ME. The dominant bacterial taxa in these three groups were Proteobacteria and Firmicutes at the phylum level. At the genus level, the bacterial communities included Lactobacillus, Paralactobacillus, Enterobacter, Pediococcus, Flavobacterium, Chryseobacterium, Pedobacter, Sphingomonadaceae, and Erwinia, furthermore, Lactobacillus, Paralactobacillus, and Enterobacter were the dominant genera in the bacterial communities. The abundance of Enterobacter tended to decrease during the mixed storage period. The total abundance of lactic acid bacteria in groups AA and AB was higher than that in group ME, but the lactic acid bacterial diversity in groups AA and AB was lower than that in group ME, and the main lactic acid bacteria present were Lactobacillus, Paralactobacillus, and Pediococcus. In conclusion, at optimum proportions DMS and CW can be kept in mixed storage by ensiling while undergoing fermentation for 60 days while maintaining good quality. The storage quality was further improved by the addition of acetic acid, and we propose that the addition of acetic acid at a dose of 0.3% would be the most conducive to the preservation of the organic components of DMS and CW, such as DM, WSC, CP and HOC.